Releasable ski binding with regulatable toe release mechanism

ABSTRACT

A ski binding to releasably hold a ski boot has a mechanism for holding the toe of the skier&#39;&#39;s boot which releases the boot when the lateral or upward forces of the boot toe in the binding reach predetermined levels. The ratio between the lateral and vertical forces necessary for release of the boot toe is fixed by the toe release mechanism and may be varied by substituting interchangable parts in the mechanism.

United States Patent Cubberley Mar. 11, 1975 RELEASABLE SKI BINDING WITI-I REGULATABLE TOE RELEASE MECHANISM [75] Inventor: Mitchell I-l. Cubberley, Nutley, NJ.

[73] Assignee: Cubco, Inc., Nutley, NJ.

[22] Filed: Apr. 2, 1973 [21] App]. No.: 347,117

[52] U.S. Cl 280/1l.35 T [51] Int. Cl. A63c 9/08 [58] Field of Search 280/11.35 T

[56] References Cited UNITED STATES PATENTS 2,616,714 11/1952 Cubberley 280/11.35 T

3,612,559 10/1971 Petersen ..280/l1.35T

Primary ExaminerRobert R. Song Attorney, Agent, or FirmThomas Cifelli, Jr.

[57] ABSTRACT A ski binding to releasably hold a ski boot has a mechanism for holding the toe of the skiers boot which releases the boot when the lateral or upward forces of the boot toe in the binding reach predetermined levels. The ratio between the lateral and vertical forces necessary for release of the boot toe is fixed by the toe release mechanism and may be varied by substituting interchangable parts in the mechanism.

4 Claims, 12 Drawing Figures RELEASABLE SKI BINDING WITH REGULATABLE TOE RELEASE MECHANISM BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to skiing apparatus and, more particularly, to apparatus which releasably binds a skiers boot to a ski.

2. Description of the Prior Art Much effort has been expended on the problem of safely securing a skiers boot to the ski with enough force to enable the skier to adequately control the skis while, at the same time, allowing the skiers boot to be released from the skis should the forces of his foot become great enough to injure him. The releasable ski bindings which hold the skiers boot to the ski must allow for release of the skiers boot in the horizontal plane when forces tend to twist the skiers foot and in the vertical plane when forces tend to lift the skiers boot.

The importance of ski bindings has become more important as developments in ski boot construction, such as molded plastic inserts, have provided evermore rigid positioning of the skiers foot within the ski boot, thereby tending to increase the danger of serious injury if the boot is not properly released from the ski when safe force limits are exceeded. In the past, the old ski bindings provided constant fixed ratios of the vertical forces to the horizontal forces necessary to release the toe portion of a skiers boot from the ski binding. Through an empirical analysis, it was found that a ratio of approximately 1.8 to l of vertical release force to horizontal release force was sufficient for the skier to maintain adequate control of his skis and still allow for safe release of his boot from the ski binding. An example of the ski bindings developed to meet these needs is shown in my previous US. Pat., No. 2,616,714, issued Nov. 4, 1952, which I incorporate by reference in this application.

The ratio of approximately 1.8 to l of vertical release problems. In order to increase the-ratio of upward to lateral release, without changing the coacting elements of the mechanism, it was necessary to reduce the lateral dimension of the fulcruming flange. However, when this lateral dimension is reduced, the moment or mechanical advantage exerted by the sideways or lateral force becomes considerably less and, accordingly, it is force to horizontal release force was developed in connection with the skiing style previously universally accepted, in which the skier places his primary weight on the balls of his feet leaning forward on his skis as he progresses downhill.

With the development of the new ski boots and new skis, new skiing positions have come into acceptance and are finding favor with a portion of the skiing public. In these new positions, the skier tends to sit back further on the tails of his skis, in other words, places less weight forward and more rearward. With this new skiing position, the ratio of vertical release to horizontal release for the toe holding mechanism must be changed to increase the vertical force necessary to release the boot in order to compensate for the greater upward force exerted on the ski binding due to the skiers leaning back further.

The ratio of the vertical to horizontal forces which release the toe holding mechanism of the ski binding is determined by the geometry of the fulcruming flange or toe post apron, as discussed in my previous US. Pat., No. 2,616,714, incorporated herein by reference. Attempts to change the ratio of vertical to horizontal release forces using existing toe release mechanisms by merely changing the dimensions or geometry of the fulcruming flange without redesigning the remainder of the toe release mechanism have presented serious necessary to increase the tension of the spring which counteracts the lateral force which acts to free the boot. Often, the spring tension must be increased to a point where the spring can no longer be directly compressed by forward forces which-can be expected during skiing, as for example, the forces produced during a sudden deceleration. The inability of the toe post spring to be directly compressed provides a significant hazard, since such direct compression is necessary in order to release the rear of the skiers boot from the ski binding during sudden deceleration.

Additionally, it was found that when the lateral dimensions of the fulcruming-flange were reduced to provide the desired release force ratios, the dimensional tolerances of the coacting parts became much more important. This was. especially so with respect to the clearance between the bottom of the fulcruming flange and the surface which coactedwith the bottom of the flange to prevent the fulcruming flange from rotating.

Additionally, it has been found that many of the toe release mechanisms commonly used have the major working components exposed and, therefore, have a tendency to freeze or to jam because they are exposed to the ice, snow and grit and freezing temperature condition that skiers normally encounter during skiing. The jamming or freezing of the toe release, therefore, provides a substantial hazard to the skier. This seizure hazard is accentuated when the dimensional tolerances of the fulcruming flange are more critical as a result of narrowing of the fulcruming flange.

SUMMARY OF THE INVENTION In order to overcome the problems of the prior art, the present invention sets forth a releasable ski binding, having a ski boot toe holding mechanism which provides regulatable fixed ratios for forces necessary to release the boot in response to upward or lateral forces exerted on the ski binding. The binding is constructed to enable interchanging of fulcruming elements in the binding to enable the skier to change the ratio of vertical to horizontal forces sufficient to actuate the toe holding release mechanism, in order to compensate for different modes of skiing.

Accordingly, it is an object of the present invention to provide a releasable ski binding which prevents premature upward release of the toe holding mechanism, when said toe holding mechanism is set for proper sidewise or lateral release.

Another object of the present invention is to provide a releasable ski binding which will hold constant at a given regulated ratio of upward to lateral force required for upward and lateral release respectively of the toe holding mechanism.

It is a further object of the present invention to provide a releasable ski binding in which the toe holding mechanism can be adapted to accommodate different styles of skiing.

Still another object of the present invention is to provide a releasable ski binding which can provide a substantially greater requirement for upward or vertical release forces than for lateral, sideways release forces necessary to actuate the toe release mechanism.

It is an additional object of the present invention to provide a releasable ski binding which can be adapted to provide the lowest release forces for the skier to keep him safely in his skis, regardless of the particular style of skiing being employed.

Another object of the present invention is to provide a releasable ski binding which allows compression of the actuating spring in a forward direction during sudden decelerations of the skier.

It is also an object of the present invention to provide a releasable ski binding which is responsive to coaction between the toe post ski binding and heel ski binding to facilitate release of the skiers boot during sudden declerations.

A further object of the present invention is to provide a releasable ski binding which does not require relatively close machining tolerances for proper functionmg.

It is still another object of the present invention to provide a releasable ski binding which is resistant to interference in the functioning of the mechanism produced by grit or other foreign substances.

A further object ofthe present invention is to provide a releasable ski binding which does not require narrowing the dimensions of elements in the toe release mechanism in order to increase the ratio of upward to sideward release forces for actuation of the mechanism.

It is still another object of the present invention to provide a releasable ski binding which can accommodate different sizes of elements in the toe release mechanism to produce different ratios of upward to sideways release forces for actuation of the release mechanism.

Additionally, it is an object of the present invention to provide a releasable ski binding with toe release mechanism which prevents snow and debris from impairing the release operation of the toe release mechanism.

Other objects and advantages will be apparent from the following description of embodiments of the invention, and the novel features will be particularly pointed out hereinafter in connection with the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of a ski binding built in accordance with the present invention, mounted on a ski and secured to a ski boot.

FIG. 2 is a top elevation ofa toe release mechanism on the ski binding shown in FIG. 1, partially in section. FIG. 3 is a side elevation of the toe release mechanism shown in FIG. 2.

FIG. 4 is an end view of the toe release mechanism shown in FIG. 2.

FIG. 5 is a cross section, taken along lines 5-5 of FIG. 2.

FIG. 6 is a top view, showing a side releasing position of the toe release mechanism.

FIG. 7 is a side view, showing the vertical upward releasing position of the toe release mechanism.

FIG. 8 is an exploded view of the toe release mechanism.

FIG. 9 is a partial view of a modified form of the invention, using a longer fulcruming flange.

FIG. 10 is a partial view of another embodiment of the invention, showing a fulcruming flange cover memher positioned inside the housing of the toe release mechanism.

FIG. 11 is a side view of the fulcruming flange cover member shown in FIG. 10.

FIG. 12 is a sectional side view of the fulcruming flange cover member mounted in the housing of the toe release mechanism.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 through 8, FIG. 1 shows a skiers boot 20 resting on top of a ski 22 and held in position on the ski by means of a releasable ski binding which includes a toe holding assembly or mechanism 36 and a heel holding mechanism 34. The boot is secured to the ski binding by means of a toe plate 28 mounted to the bottom of the ski boot sole 24 near the toe portion of the boot 26, and the boot heel 30 is secured to the heel holding mechanism 34 by means ofa heel plate 32 fastened to the bottom of the heel.

The functioning of the heel holding mechanism is more thoroughly described in my US. Pat., No. 2,616,714, incorporated herein by reference, but will briefly be described as follows. The heel holding mechanism consists of a heel clamp frame 38 connected to a bottom plate 40 which is secured to a ski by means of any convenient fastening means, such as screws 41. Heel clamp fastening arms 42 are pivotally connected by pivot pin 46 to a heel clamp lever 44 so that the heel clamp fastening arms can be moved into and out of engagement with heel plate 32 to hold the heel in position. A thrust bolt 48 is connected with the heel clamp lever and heel clamp fastening arms and bears against these elements to hold them in position during normal skiing operation. A bearing surface 50 extending upward from the back of the heel bottom plate 40 supports the back end of the heel thrust bolt. The bolt is held in position by a heel clamp tensioning spring 52 which is adjusted by manipulating heel clamp spring adjusting nut 54 to loosen or tighten the tension of the spring 52 against the heel clamp fastening arms to keep the arms in engaged position with the boot of the heel. Should a vertical force be exerted by the heel on the heel clamp fastening arms which is greater than the force which can be counteracted by the heel clamp tensioning spring 52, then the arms will pivot upward, releasing the heel of the skiers boot.

The toe release mechanism, generally indicated at 36, comprises an outer covering shell or housing 56 which is fastened to the ski by means of screws 64 which extend through screw passages in the skirt 58 of the shell. When the shell is to be mounted on the ski, screws are first fastened through slots 62 in the boot side of the skirt and the shell is placed in its proper position for coaction with the ski boot and then screws 64 are placed in the screw holes at the front or head end of the shell. An access slit 66 is located at the top of the shell to allow for limited access to the internal workings of the toe release mechanism within the shell.

The element which actually engages the toe area of the boot referred to as the toe post, generally indicated at 70, is mounted within shell 56. The toe post includes an engaging cylindrical end or stud 72 with a stop flange 74 positioned on it. The stud is intended to be received in the seat, in the form of a hole 78, in the lip 76 of the toe plate 28 which is fastened to the boot, as previously mentioned. The toe post element includes a spherical section 80 which substantially avoids contact with the passage 81 to allow full freedom of movement of the toe post body in response to forces exerted on it by the toe plate 28 of the boot. The other end of the toe post element is formed into a pin 82 which is adapted to seat in the socket 86 in the end of an adjustable thrust bolt 84 which positioned in the shell 56 of the toe release mechanism. As most clearly seen from FIGS. 6, 7 and 8, the adjustable thrust bolt 84 is mounted within the shell 56 and tensioned in position within the shell by means of a compression spring 94 which at one end bears against the front wall 68 of the toe release assembly shell 56, and bears against an adjusting nut 90 threadably mounted onto threaded section 92 of the adjustable thrust bolt. The tension exerted by the spring 94 on the thrust bolt is adjusted by rotating the adjusting bolt head 88 with a screwdriver or any other convenient means to move the position of the adjustment nut to either extend or compress the compression spring. Depending upon the tension exerted by the spring, the toe post element will be relatively loosely or tightly held in position within the shell of the toe release mechanism, due to the action of the spring and the fulcruming flange or toe post apron 96 which is connected to the toe post body and whose function will now be explained.

The fulcruming flange or toe post apron, generally indicated at 96, is fixedly attached through a passage 98 to the main portion of the toe post body by any convenient fastening means, as, for example, by shrink fitting and peening over as is the case in the present embodiment of the invention. As shown in FIGS. 1 through 7, the toe post apron 96 has side faces 100 and a bottom face 102 and has engaging points 104 at the four corners ofthe apron, which are adapted to contact the inner surface 105 of the front wall 60 of housing 56 to provide a fulcruming point about which the entire toe post body will pivot when the forces from the skiers boot exerted on the toe post engaging cylinder become great enough to move the toe post against the tension forces exerted by the spring 94.

As shown in FIG. 5, the geometry of the dimensions of the toe post apron or fulcruming flange determine the ratio of the upward forces to lateral forces that are necessary to release the toe holding mechanism of the ski binding. The fulcruming distance for lateral forces that is exerted through the toe post body in response to forces transmitted to the toe post engaging cylinder end 72 is determined by the distance A, which is the distance the closest point on the circumference of the toe post apron passage 98 to the lateral edge of the toe post apron 100. Similarly, the distance B, the distance from the closest point on the circumference of the toe post apron passage 98 to the bottom 102 of the toe post apron 96 will be the fulcruming distance for forces transmitted from the toe post engaging cylinder which tend to act against the force of the spring 94. It has been found that a ratio of B to A of 1.8 to 1 was found suitable to give the proper ratio of upward release force to lateral release force for the ski binding using the heretofore universally accepted skiing style.

It can be readily understood that the attitude or position of the toe post apron or fulcruming flange with respect to the front wall is critical in maintaining the proper relationship between lateral and horizontal release forces sufficient to actuate the release mechanism. If the toe post apron were to rotate in its mounting, then the location of the contacting corners would change, changing the fulcruming ratios A and B.

In my prior U.S. Pat. No. 2,616,714, the fulcruming flange was held in position by abutting the lower end 102 of the fulcruming flange or toe post apron 96 with the upper surface of the ski or bottom plate which was part of the toe release mechanism. However, this can no longer be done, since the ski mechanism must now accommodate toe post aprons or fulcruming flanges of varying length. For example, as shown in dotted lines in FIG. 5, a longer toe post apron 110 having a bottom surface 112 is in contact with the ski and has a fulcruming distance for vertical release of a ski shown at C.

This type of apron would have a ratio of approximately 2.6 to l, which empirically has been found to be a proper ratio for upward release to a lateral release forces for the modern trend in skiing which favors the leaning backward posture and, therefore, applying greater upward forces against the toe release mechamsm.

Accordingly, it is necessary to provide means to keep the toe post apron or fulcruming flange from rotating with relation to the inner face 105 of the boot end 60 of the shell. Ths is done by means of the side walls 116 in the shell which are dimensioned to closely fit about the side walls of the toe post apron or fulcruming flange 96 or any other flange to be installed, so that the flange is held in a fixed attitude to maintain the critical dimensions of B or C with respect to A.

As shown in FIGS. 5 and 9, the boot end of the shell by meansof its side walls can accommodate toe post aprons or fulcroming flanges of any dimension from the relatively short aprons having a bottom edge 102 to relatively long aprons having a bottom edge 112. Note that the bottom 114 of the front face of the boot side of shell 60 is perpendicular down to the very bottom of the front wall 60 to insure that the fulcruming points or contact points 102 at the bottom of the fulcruming flange will have an adequate area to work against.

In FIGS. 8, 10, 11 and 12, is shown another embodiment of the invention in which an apron retaining liner 118 is mounted within the shell 56 against the inner front wall 105 to provide an even more secure means to keep the toe post apron from rotating. The apron retaining liner 118 is fastened through the passage 81 in the front wall of the shell by means of a circular flange 120 which extends through the passage 81 and is then peened over to hold the apron retaining liner 118 fixed. The attitude of the liner is kept absolutely vertical by means of a plurality of small knuckles or feet 122 which extend against the front wall 105 to insure that the liner is maintained in a proper attitude. The liner 118 has side walls or flaps 126 which are adapted to engage the sides of a long toe post apron such as shown in FIG. 9, or a shorter toe post apron 96 shown in FIG. 5. Additionally, a bottom flap 124 is provided in the liner to protect the top of the ski and insure that aprons which are too long are not used.

The operation of the device has been explained previously and will only be briefly restated. When force exerted by the toe of the boot is transmitted via the toe plate 28 of the boot, the engaging cylindrical portion 72 of the toe post mounted in the receptacle 78 of the bent-up lip 76 of the toe plate 28, will receive the transmitted force. The dimensions of the toe post apron or fulcruming flange 96 or 110, depending upon which flange is installed, will then determine the mechanical advantage that the force transmitted from the-boot must work against. The mechanical advantage comes into play because of the force exerted by the adjustable thrust bolt 84 through socket 86 on to the pin 82 of the toe post, which tends to urge and hold the toe post in the proper centered position, as shown in FIG. 3. The ratio of the fulcruming forces in the horizontal to vertical plane will be determined by the distances between the toe post apron passage and the contracting points of the toe post apron as shown by the relative distances A and B and C, depending upon the toe post apron in use.

Adjustment of the overall tension applied in both horizontal and vertical directions is provided by threading the adjustable thrust bolt to cause the adjusting nut 90 to expand or contract the tensioning spring 94.

Change in the ratio of vertical to horizontal force required for actuation of the toe release mechanism is accomplished by changing the toe release apron. This is done by unscrewing the shell 56 from the ski and backing off the adjustable thrust bolt 84 until the toe post engaging pin is no longer in contact with the socket 86 in the end of the thrust bolt 84. The entire toe post and toe post apron or fulcruming flange can then be lifted out of the toe release mechanism and a new toe post body and apron or fulcruming flange can be readily inserted and the apparatus then reassembled.

It should be pointed out that the apron retaining liner 118 could also be adapted for use with the existing open type toe release mechanisms to prevent rotation of the apron and thereby accommodate different apron sizes while insuring that the apron would be held in proper operating position.

Another advantage that should be pointed out is that the entire toe post mechanism is completely enclosed by shell 56. This prevents or tends to seriously reduce the incidences ofjamming due to freezing or clogging of the mechanism from snow, ice and dirt which normally have a tendency to become heaped upon the toe release mechanism of the ski during normal skiing operations.

It will be understood that various changes in the details, materials and arrangements of parts which have been herein described and illustrated in order to explain the nature of the invention may be made by those skilled in the art within the principle and scope of the invention, as expressed in the appended claims.

What is claimed is:

l. A ski binding having a toe release mechanism comprising:

a toe post member having:

a first portion adapted to engage a toe plate of a ski boot; and a second portion adapted to engage resilient means; resilient means contacting said second portion of said toe post member to urge said first portion of said toe post member toward engagement with said toe plate; fulcruming means connected to said toe post member and having two side surfaces, said fulcruming means coacting with said resilient means to urge said first portion of said toe post member into position for operative engagement with said toe plate; a housing adapted to be secured to a ski and enclosing at least a portion of said toe post member and said resilient means, said housing having; a front wall providing a fulcruming surface for said fulcruming means; a rear wall engaged by said resilient means; and two side walls disposed on opposite sides of said front wall and continuous with said rear wall; said fulcruming means dimensioned to provide a ratio of fulcrum effect against vertical and lateral displacement of said first portion of said toe post member; and said housing dimensioned so that the said side walls of the housing coact with the said surfaces of the fulcruming means to prevent rotation of the fulcruming means with relation to the said front wall of the housing. 2. The ski binding according to claim 1, wherein said resilient means comprise:

a thrust member contacting said second portion of said toe post member; and spring'means contacting said thrust member and said rear wall of the housing to urge said thrust member against said second portion of said toe post member. 3. The ski binding according to claim 2, wherein: said second portion of said toe post includes pin means; and the thrust member has socket means adapted to receive said pin means. 4. The ski binding according to claim 3, wherein said thrust member is adjustable to adjust the tension of said spring means. 

1. A ski binding having a toe release mechanism comprising: a toe post member having: a first portion adapted to engage a toe plate of a ski boot; and a second portion adapted to engage resilient means; resilient means contacting said second portion of said toe post member to urge said first portion of said toe post member toward engagement with said toe plate; fulcruming means connected to said toe post member and having two side surfaces, said fulcruming means coacting with said resilient means to urge said first portion of said toe post member into position for operative engagement with said toe plate; a housing adapted to be secured to a ski and enclosing at least a portion of said toe post member and said resilient means, said housing having; a front wall providing a fulcruming surface for said fulcruming means; a rear wall engaged by said resilient means; and two side walls disposed on opposite sides of said front wall and continuous with said rear wall; said fulcruming means dimensioned to provide a ratio of fulcrum effect against vertical and lateral displacement of said first portion of said toe post member; and said housing dimensioned so that the said side walls of the housing coact with the said surfaces of the fulcruming means to prevent rotation of the fulcruming means with relation to the said front wall of the housing.
 1. A ski binding having a toe release mechanism comprising: a toe post member having: a first portion adapted to engage a toe plate of a ski boot; and a second portion adapted to engage resilient means; resilient means contacting said second portion of said toe post member to urge said first portion of said toe post member toward engagement with said toe plate; fulcruming means connected to said toe post member and having two side surfaces, said fulcruming means coacting with said resilient means to urge said first portion of said toe post member into position for operative engagement with said toe plate; a housing adapted to be secured to a ski and enclosing at least a portion of said toe post member and said resilient means, said housing having; a front wall providing a fulcruming surface for said fulcruming means; a rear wall engaged by said resilient means; and two side walls disposed on opposite sides of said front wall and continuous with said rear wall; said fulcruming means dimensioned to provide a ratio of fulcrum effect against vertical and lateral displacement of said first portion of said toe post member; and said housing dimensioned so that the said side walls of the housing coact with the said surfaces of the fulcruming means to prevent rotation of the fulcruming means with relation to the said front wall of the housing.
 2. The ski binding according to claim 1, wherein said resilient means comprise: a thrust member contacting said second portion of said toe post member; and spring means contacting said thrust member and said rear wall of the housing to urge said thrust member against said second portion of said toe post member.
 3. The ski binding according to claim 2, wherein: said second portion of said toe post includes pin means; and the thrust member has socket means adapted to receive said pin means. 